The present invention relates to an apparatus for purifying urban and industrial waste water by means of physical chemical treatment. More particularly, the present invention relates to such an apparatus in the configuration of a compact or integral unit containing therein serially connected compartments for neutralization and coagulation, for flocculation, and for lamellar decanting of the treated liquid and thickening of the sludge.
In most previously known systems for the physical chemical purification of waste water, for example sewage, the operations of neutralization and coagulation, of flocculation, and of decanting are performed in separate units. Such systems are inherently expensive to construct and maintain the furthermore occupy a considerable amount of space.
Accordingly, there have been prior art attempts to design an apparatus which is more compact by combining various of the above individual units into a single apparatus. However, such prior art attempts to construct a compact apparatus employing physical chemical treatment methods have so far met with only limited success. Specifically, such known compact systems are generally employable only for the physical chemical treatment of river water to obtain drinking water. That is, such known systems are in actual practice suitable only for treating water which is relatively unpolluted. Such known systems do not allow for the evacuation of heavy substances, such as sand and other materials suspended in the water to be treated. This is manifestly disadvantageous in the treatment of heavily polluted water such as urban and industrial waste water. Furthermore, evacuation of sludge from such known systems can only be achieved by periodically stopping the operation of the entire apparatus.